Oconomowoc, WI

Oconomowoc tap water meets EPA legal standards (Maximum Contaminant Levels). However, 9 contaminants are present above independent health guidelines, which are often stricter than legal limits. 19 contaminants have been detected in the water supply, including Lead, Nitrate, Arsenic, Copper, Radon. View the detailed report for each water system to see specific levels and how they compare to both legal limits and health guidelines.

Monitoring has detected 19 contaminants in Oconomowoc's water supply: Lead, Nitrate, Arsenic, Copper, Radon, Radium, Uranium, Gross Alpha Radiation, Total Trihalomethanes, Haloacetic Acids (HAA5), Atrazine, Nickel, Selenium, Mercury (inorganic), Barium, Fluoride, PFHpA (Perfluoroheptanoic Acid), Methyl Tert Butyl Ether, PFBA (Perfluorobutanoic Acid). Additionally, 6 PFAS compounds have been detected at trace levels. 9 exceed health guidelines. See individual system reports for concentrations relative to EPA limits.

Yes. 6 PFAS compounds have been detected in Oconomowoc's water supply at trace levels. PFAS are sometimes called "forever chemicals" because they do not break down in the environment. The EPA has set Maximum Contaminant Levels for several PFAS compounds. View the detailed report for specific concentrations.

Yes. Oconomowoc water has a hardness of 360 mg/L (very hard). Hard water is not a health concern but can cause scale buildup in water heaters and appliances, reduce soap effectiveness, and leave mineral deposits. Water softeners or conditioning systems can address hardness.

Oconomowoc's drinking water comes from groundwater wells that draw from underground aquifers. The water is treated and tested according to Wisconsin DNR and EPA requirements before distribution. Oconomowoc is served by 9 water systems, the largest being OCONOMOWOC WATERWORKS (serving 15,805 people).